This invention relates to an improved process for treating metal chlorides and especially such metal chlorides arising as byproducts from the chloride process for making TiO.sub.2.
Large amounts of metal chlorides arise as byproducts from various industrial processes. For example, in the chloride process for making TiO.sub.2, titanium bearing material or ore is chlorinated to produce TiCl.sub.4 and other metal chloride byproducts. Subsequently, the TiCl.sub.4 is separated from the byproducts and is oxidized to the desired TiO.sub.2. The metal chloride byproducts are highly acidic and often contain iron chlorides as the major ingredient. While some of the byproducts can be used as a flocculant to treat waste water, large amounts must be disposed of by neutralization, land filling, deepwelling, etc.
Many processes have been proposed to neutralize and/or stabilize metal chloride byproducts. However, such processes appear to be deficient because they are both expensive and produce a product which still must be disposed of by landfill or other means.
The following information is provided which may be of interest in regard to this invention:
U.S. Pat. No. 4,229,399 discloses a process wherein solid mixtures of certain metal chlorides are mixed with certain alkaline substances followed by the addition of water. It is stated that the resulting product is substantially insoluble in water.
U.S. Pat. No. 4,375,986 discloses a process for neutralizing acidic waste material consisting of mixing the waste material with fly ash, neutralizing the resulting mixture with lime or other calcium containing materials, and adding a calcium containing binder such as lime or portland cement.